Thirty years after creation of the posttraumatic stress disorder (PTSD) diagnosis, its literature could still benefit from standardization of traumatic events. The authors report the type and frequency of traumatic events found in the mainstream PTSD literature using a bibliometric approach, and propose a categorization based on the terms used for their description. Articles containing [ptsd OR “stress disorder*”] in the title field found in the ISI/Thompson Reuters (Philadelphia, PA) 1991–2006 database were classified according to the event studied. The authors describe each event's absolute and proportional figures, and construct a categorization of the events. The bibliometric analysis of PTSD literature is helpful in planning research, and the proposed categorization may represent an advance toward the standardization of traumatic events.